The present invention relates to a novel ink-jet recording film or, more particularly, to an ink-jet recording film capable of exhibiting good fixing behavior for water-base inks or, in particular, pigment-containing water-base ink and also exhibiting excellent water resistance.
Along with the remarkable prevalence of the application technology of computers in recent years, it is now widely and frequently practiced to make a print-out record of the computerized data by using a printer. Various types of printers are now under use for this purpose including dot-impact printers, laser printers, thermal printers and ink-jet printers, of which ink-jet printers are employed most widely by virtue of the outstandingly low machine noises and the low operation costs. While the sheet material on which the ink-jet recording is made by using an ink-jet printer can be a plain paper sheet or coated paper sheet for most purposes, it is also frequently the case with a special purpose that ink-jet recording is made on a specific ink-jet recording film prepared by coating a surface of a plastic film as a substrate film with a specifically formulated coating composition comprising a hydrophilic polymeric resin to form an ink-receptive layer.
Various proposals and attempts are made relating to the formation of the above mentioned ink-receptive layer on the substrate surface for an ink-jet recording film. For example, Japanese Patent Publication 6-4247 proposes an ink-jet recording film having an ink-receptive layer containing polyvinyl alcohol and polyvinyl pyrrolidone. Japanese Patent Kokai 5-262028 discloses an ink-jet recording film consisting of a substrate film and a multi-layered ink-receptive layer composed of at least two layers, of which the outermost layer is formed from a coating composition containing a polyvinyl acetal resin and the undercoating layer to the outermost layer contains a water-soluble resin. Further, Japanese Patent Kokai 5-286228 proposes a double-coated ink-jet recording film, of which a substrate film is provided, on one surface, with a dye-absorbing layer and, on the other surface, with a layer of a water-swellable resinous material such as a mixture of polyvinyl alcohol and polyvinyl pyrrolidone. Thus, it is the prior art in the technology of ink-jet recording films to use polyvinyl alcohol, polyvinyl acetal, polyvinyl pyrrolidone or a combination thereof as the resinous constituent in the ink-receptive layer.
When the ink-receptive layer of an ink-jet recording film is formed from a combination of these hydrophilic resins, however, serious defects are unavoidable of the recording film including the low water resistance of the ink-receptive layer and tackiness of the surface of the ink-receptive layer if not to mention the relatively poor performance not to fully satisfy the requirements for ink-jet recording films that the ink droplets formed by the jet of ink do not unduly spread to have an increased diameter of the ink dots, that each of the ink dots has a profile as close to a true circle as possible and that the profile of the ink dot is generally circular without rugged contour not to show a polygonal or asteriated pattern resulting in a decrease in the pattern resolution and sharpness of the image lines.
With an object to overcome these defects, a proposal is made in Japanese Patent Kokai 8-156396 for an ink-jet recording film having, on the surface of a substrate film, successively laminated layers including (A) an ink-receptive layer formed from a composition comprising, as the principal ingredients, polyvinyl alcohol, polyvinyl acetal or a combination thereof and a fine particulate material and (B) an overcoating layer containing a dot profile controlling agent but this recording film is still not quite satisfactory in respect of fixing of the ink.